Multiple cross-site scripting (XSS) vulnerabilities in Kayako SupportSuite 3.20.02 and earlier allow remote attackers to inject arbitrary web script or HTML via (1) the sessionid parameter in a livesupport startclientchat action to visitor/index.php; (2) the filter parameter in a news view action to index.php; or the Full Name field in a (3) account creation, (4) ticket opening, or (5) chat request operation.